Unjoined domain, now cannot login

We were sent some Surface Pro 2 Tablets at work. They were already setup with the programs we needed, however they were not behaving correctly. Kept getting network errors for the domain, as everything else on the network was working but that.

So silly me (apparently at least) unjoins our domain, restarts, and now I cannot login for anything in this world. I cannot get any other user accounts to show up but the last person who logged in, who was an administrator on tablet under our domain, and the password simply does not work. I have tried restarting in safe mode with and without network and that doesn't work because it won't recognize the password for the user. So I thought system restore would work but apparently I need to login to the account to do that as well. Also tried rebooting to the command prompt. I apparently need to login for that as well. I have tried rebooting into a password recovery/reset disc but I cannot get it to boot to the cd, or at least if it is, it's certainly not reading the disc (which I knows works for XP & 7). I cannot do a reset password usb because alas, I need to be able to login to be able to create one of those. I've looked at several online things but most of them start with "you need to be logged in".

So I am at a complete loss of what to do now. Can anyone help me?

Well, I have seemingly fixed my problem, without actually fixing anything. Apparently when I reset the local admin account's password (as I had no idea what it was), it made that the password for the user that was currently logged in. Why? I have no idea. But at least I can log in now.

It does warn you right before you unjoin a machine from a domain that you will need to have a local administrator user account and password to log back in.

Oh I know, which is why I reset the local admin account password, but when it came back up, it would not let me switch to that user. The arrow to do so was not there.